Composition for oilless bearings and process for producing same



3 Patented June UNITED STATES. PATENT-OFFICE JOHN O. CARREY, OF ST. LOUIS, MISSOURI, ASSIGNOR 'IO CARREY-MORSE ENGINEER IETG COMPANY, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI COMPOSITION FOR OILLE SS BEARINGS .AND PROCESS FOR ERODUCING SAME 1T0 Drawing.

This inventionrelates to a new composition that is'intended to be used for 01 less bearings.

a One object of my invention is to provlde 5 a metal hearing, which, in addition to being self-lubricating, is of such a character that it will not heatup' easily, it will not cut or wear rapidly and it can be ,used successfully as an end thrust bearing. which oooperates with a thrust collar on a rotating shaft to form a gas-tight seal around said shaft. 7

Another object is to provide a novel process for producing the composition used to form such a bearing.

The new composition that I have devised is composed of Babbitt metal, finely divided.

graphite, finely-divided mica and sulphur, mixed preferably intapproxim ately the fol 2 lowing proportions: i. e.-

1 part Babbitt metal part graphite part mica 4 part sulphur tit of flour a bite e ual to ap roximatel on -half the n fount 3f Babbitt? metal and a quantity of ground mica equal to approximately one-half the amount of Babbitt metal, .said mixture being stirred or agitated in such a wa as to insure a thorough and uniform distrlbution of the graphite and mica throughout the entire mass of Babbitt metal, and being maintained at a temperature at or slightly above the melting point of Babbitt metal, during the mixing operation. The temperature of this mixtureis then reduced slightly and a small amount of paraflin and a quantity of sulphur equal to approximate.- ly one-fourth the amount of Babbitt metal are added to the mixture and thoroughly distributed through the same, the mixture being maintained at a sufliciently low temperature during the time the paraflin and sulphur are being added to same to eliminat Babbitt metal.

to and thoroughly mix with the same a quan-- Application filed October 26, 1925. Serial No. 65,046.

' paraifin to be mixed with same by a stirring operation, and it will not be high enough to cause the sulphur to flash. The quantity of parafiin that is added to the mixture may vary within certain limits, but in most instances I use a quantity of paraflin equal to approximately one-eighth the amount of After the sulphur and paraflin have been mixed with the other ingredients, as above described, the mixture is introduced 'into a heated die or mold consisting of a cylinder provided with a plunger, and it is then subected to sufiicient pressure or impact to condense the mass and cause the ingredients constituting same to be combined into a solid bearing that is hard enough to have great wear-resisting properties and which is of sufficiently fine grain and texture to roduce a smooth, non-porous surface, whic when arranged in engagement with a 00-0 erating smooth surface, will form a gas-tight joint.

The plunger has a working fit in the cylinder, and accordingly, when the plunger is forced into the cylinder, most of the paraflin, which is then in a liquid state, will escape through the space between the plunger and cylinder, thus leaving only a slight traceof the parafiin in the composition. The temperature of the die or mold in which the composition is compacted or solidified may vary within certain limits, but it should be considerably below the melting point of Babbitt metal.

Due to the fact that the composition above described contains graphite, mica and sulphur, the bearing formed from said composition will be self-lubricating, and another desirable feature of saidbearing is that it will not heat up ra idly, due to the presence of the sulphur m t e composition. There is only a slight trace of the paraflin left at the completion of thecompacting or solidifying operation, but the parafiin performs a very important function in the operation of pressing, impacting or compressing the composition, in that it tends to hold the granules of the composition together during the a the shaft which contacts with the bearing. p

Having thus described my invention,what

I claim as new and desire to secure by Letters Patent is:

1., A composition composed of the following ingredients, mixed in approximately the proportion specified: 1 part Babbitt metal, A; part finely-divided temperature of said mixture slightly and i then adding to same a small quantity of paraflin and a quantit mately equal to oneourth t e amount of Babbitt metal, the parafiin and sulphur being stirred through the mixture while it'is in a plastic state, and thereafter introducing said mixture into a heated mold ordie and subjecting it to pressure or impact so as to condense the mixture into a solid body.

' JOHN O. CARREY.

for oilless bearings graphite, part finely-divided mica, part sulphur. v

2. A process for producing a composition I for bearings, characterized by adding finely divided graphite,

and finely-divided mica to a mass ofmolten Babbitt metal and thoroughly distributing the same through said metal, and thereafter incorporating sulphur in said mixture while the mixture is maintained at a temperature low enough to prevent the sulphur from flashing. j

3. A process for produclng a composition for bearings, characterized by melting a quantity ground mica, one-half the amount of Babbitt metal and of Babbitt metal, adding flour graphite and ground mica to saidmetal and distributin the same throughout the mass of metal while the metal is in a molten state, and thereafter reducing the temperature of said mixture slightly and adding sulphur and a small quantity of paraflin to same.

4. A process forproducing an oilless bear-t ing characterized by adding finely-divided graphite and finely-divided mica to a mass tributing said ingredients through said metal, adding sulphur and a small quantity of parafiin to sald mixture when the mixture is at a temperature low enough to prevent the sulphur from flashing, and thereafter subjecting said mixture to pressure or impact so as to compact or condense the ingredientsinto a solid body. a

5. .A process for producing an 'oilless bearing, characterized by melting a quantity of Babbitt metal, adding to said mass an amount of flour graphite and an'amount of eachequal to approximately thoroughly distributing said graphite and mica through the molten metal, reducing the of molten Babbitt metal and thoroughly disof sulphur approxiiot 

